Exhaust systems for internal combustion engines include exhaust manifolds connected to cylinder heads of the engine. The exhaust manifolds collect post-combustion material (e.g., exhaust gas) from multiple cylinders of the engine and deliver the material to an exhaust pipe. In operation, exhaust manifolds are subject to highly variable temperatures. Temperature variations cause the exhaust manifolds to expand and contract, which may stress and ultimately damage the manifolds, seals, and other components. Thermal expansion may be particularly problematic for large engines with correspondingly long exhaust manifolds. To that end, exhaust systems for some engines utilize exhaust manifolds that are separated into several sections. The sections are coupled together using a flexible coupling, such as a bellows, that permits expansion and contraction between the sections.